Known apparatus and methods for testing skis for stiffness or resistance to bending function on the principle of placing a pair of skis face-to-face or bottom-to-bottom and then applying forces between the skis. For example, in the U.S. Pat. No. 4,195,532, to Pauls, a C-clamp form of force-applying means is used to squeeze the skis together at midportions thereof and then to read a gage associated with the clamp. In the U.S. Pat. No. 3,964,300, to Howe, the pair of skis are clamped tightly together at their opposed midportions, and then a gage is inserted between the diverging front end portions and a reading taken on the gage. The two forms of prior art just noted have in common the testing of both skis simultaneously and testing for bending stiffness only.
According to the present invention, each ski is tested individually and, further, is tested in torsion as well as in bending, thus enabling a better determination of the suitability of the ski to a particular user and/or to particular conditions expected to be encountered in use. The present apparatus is simple to use and may be inexpensively constructed. It preferably comprises an elongated support alongside which the ski is placed in general parallelism. The support carries a clamp or the like which securely engages a portion of the ski intermediate it ends, leaving one end portion projecting cantilever fashion beyond the clamp. In its simplest form, a fluid motor applies force between the support and the cantilevered end to stress the ski in bending through a preselected amount, and the force exerted by the motor is measured, as by a load cell, for example. This motor is deactivated; and a second motor, for example, engages a lever arm temporarily clamped to the cantilevered portion of the ski; and the motor is extended to stress the ski in torsion about its lengthwise axis. The degree of torsional flexing is preselected, and again a reading is taken of the force exerted by the twisting motor to twist the ski to that degree. The parts associated with the support for engaging the ski are fashioned so the ski may be inverted and both end portions checked as aforesaid.
Further features and advantages of the invention will be seen as the description of a preferred form of the invention progresses.